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Clarification about ClinicalTrials.gov

By Deborah A. Zarin and Tony Tse
May - June 2013
Volume: 35, Issue: 3

Groman and Sugarman’s commentary “The Presidential Bioethics Commission’s Database of Human Subjects Research” (March-April 2013) reviews the findings of the U.S. Presidential Commission for the Study of Bioethical Issues 2012 Report,Moral Science: Protecting Participants in Human Subjects Research, and describes the cross-sectional project-level data collected from Common Rule departments and agencies that was recently released by the commission. Specifically, they discuss the need for a single, ongoing source of information about federally funded studies of human subjects. However, the commentary mischaracterizes ClinicalTrials.gov, and thereby understates its utility as a source of information.

Despite its name, ClinicalTrials.gov is not limited to clinical trials (or interventional studies) but is open to all biomedical or health related study of human subjects. As of March 20, 2013, 18% (26,292) of the registered studies were observational (e.g., natural history, epidemiology).

The article by Groman and Sugarman states that ClinicalTrials.gov “does not extend to other types of research with humans (p. 18)” such as “behavioral research.” In fact, ClinicalTrials.gov is not limited by intervention type. Although many of the over 142,000 (and growing) registered studies involve drugs and medical devices, there are studies of all types of interventions, including surgery, other medical procedures, and “behavioral interventions,” such as psychotherapy and lifestyle counseling. As of March 20, 2013, nearly 8% (10,897) of the registered studies included at least one “behavioral” intervention.

Finally, the authors assert that “ClinicalTrials.gov does not collect funding information. (p. 18)” In fact, ClinicalTrials.gov allows for the reporting of specific funding information, including the funding organization(s) and specific grant or contract number(s) for each study.

As federal departments and agencies move forward to develop or refine methods for tracking their studies of human subjects, it is important that they have an accurate view of the capacity of existing databases. ClinicalTrials.gov is organized by “study.” Each unique study is described using structured, common data elements within its own record in the database; and each study is assigned a unique identifier (the NCT Number). Funding databases, on the other hand, tend to be organized by grant, contract, or other funding “event.” It is difficult to use such databases to track or enumerate studies, since a study may have multiple funding sources at any one time, and may also involve different funding sources over time.

We believe that a systematic and thoughtful examination of current database structures and associated policies would enable agencies to make the best possible decisions about methods for improving the public reporting of studies involving human subjects. For studies within the biomedical or health domain, agencies might consider the benefits and limitations of developing their own databases versus incentivizing reporting to ClinicalTrials.gov. Similarly, for studies outside the scope of ClinicalTrials.gov (e.g., economic or educational studies) agencies might consider the pros and cons of developing a centralized registry (e.g., similar to ClinicalTrials.gov) versus a search portal for multiple agency-specific databases.

Regardless of the path chosen, collaboration on common data elements and harmonized definitions and procedures (e.g., reporting of studies receiving funding from several agencies to prevent multiple counting and reduce burden for data providers) will prove essential to achieving the goal of having an accurate listing of federally funded human subjects research.

Research using ClinicalTrials.gov has already led to new insights into the “clinical research enterprise.” Findings from this work have focused attention on efforts to improve scientific methods and ethical oversight. The ability to examine the full range of human studies funded by the federal government will likely yield enormous opportunities for assessing and improving ethical and scientific oversight of human research.